During the operation of a towed mower which trails behind a front tractor or mower, it is desirable to maintain the towed mower at a constant operating level so that its cutting mechanism will cut the grass and other foliage at a constant height. When the self-driven powered mower and towed mower are driven along a straight line, the towed mower typically maintains its preset height from the ground surface so that a constant depth cut of the foliage is maintained; however, when the powered mower is turned so that the assembly operates in a curve, the towed mower is angled laterally with respect to the powered mower in trailer fashion. The tendency of the towed mower when operating through a curve is that the front portion of the mower tends to dip closer to the ground surface. This has the effect of shortening the height of the foliage as it is cut by the cutting blades of the towed mower, and in some instances, the front portion of the housing or framework of the towed mower gouges into or scrapes the surface of the earth, causing scalping of the grass, disruption to the mowing operation and possible damage to the mower.
In some instances, the mower operator can anticipate the dipping problem of the towed mower as the operator begins to turn into a curve and the operator can raise the towed mower slightly away from the ground so as to avoid an improper cut or scraping the ground with the towed mower. However, this requires close attention of the operator and certain operator skills that must be developed. Even with an experienced operator, the height adjustment applied to the towed mower when operated in a turn usually is not perfect, resulting in problems such as previously described.